A clutch can take many forms but generally provides selective transmission of torque between an input and an output. Each clutch may be configured to only transmit torque when desired. For example, a clutch present in a manual transmission vehicle is switchable to transmit torque from an engine to an output shaft only when engaged in a gear selected by a driver. The transmission is otherwise in a neutral position in which the engine is effectively disconnected from the wheels.
In other situations, the characteristics of a clutch may be dictated by the desired behavior given foreseeable circumstances. In one example, a clutch may be used in situations where a component may be power driven by a motor or manually moved by an operator. A power-driven vehicle tailgate is one example of this situation. In particular, many trucks today include power-assist or power-driven tailgates which can be electronically moved between opened and closed positions or manually rotated by an operator. In this situation, there is a need for a clutch which allows freewheel rotation of the tailgate to allow for the manual operation in addition to locked rotation in either direction when a torque is being applied by a driving motor. In addition, when a driving torque is being applied, the clutch should allow for freewheel rotation in the direction of travel which assists the rotation and resist rotation in an opposite direction to transmit a torque back through to the motor.
Current clutch configurations do not provide all of these parameters in a small envelope which would render it usable in conjunction with a tailgate or other similar driven element. The present disclosure is directed to overcoming one or more problems of the prior art, including providing a clutch in a compact form capable of achieving all of the desired characteristics for relative rotation of an element such as a vehicle tailgate.